Constant-drive radial drill



P 1929- D. c. KLAUSMEYER ET AL 1,727,606

' consiumi DRIVE RADIAL DRILL F iled March 25, 1925 4 Sheets-Sheet 1 anvento w 32 Suez/41 W Sept. 10, 1929.

D. c. KLAUSMEYER ET AL 1,727,606

CONSTANT DRIVE RADIAL DRILL Filed March 23, 1925 v 4 Sheets-Sheet 2 -2- -I- ,....--ttE.

lllllllllllll llllllllllllllll' llllill aI \M w Sept. 10, 19 9- D; c. KLAUS'MEYER ET AL 1,72

CONSTANT DRIVE RADIAL DRILL Filed March 23, 1925 U 4 Sheets-Sheet 3 1/1/10 IIIIIIIl/II fijavwmtow M 351 abho'r/fiw W p 1929- D. c. KLAUSMEYER Er AL 1,727,606

CONSTANT DRIVE RADIAL DRILL Filed March 23, 1925 4 Sheets- Sheet 4 O I .9 a

anveucow Patented Sept. 10, 1929.

UNITED STATES PATENT "OFFICE;

DAVID C. KLAUSMEYER AND HENRY 'M. NORRIS, OF CINCINNATI, OHIO, ASSIGNORS TO THE CINCINNATI BICKFOBD TOOL COMPANY, OF CINCINNATI, OHIO, A COR- PORATION OF OHIO.

CONSTANT-DRIVE RADIAL DRILL.

- Application filed March 23, 1925. Serial No. 17,605.

This invention relates to radial drilling and tapping machines and it deals more particularly with the means for actuating the various mechanisms thereof such, for exam-,

ple. as the arm elevating and lowering mecln anism. the drill-head translating mechanism, the spindle rotating mechanism and the spin dle feeding mechanism.

Machine tools of this character are usually constructed with \a base, an upright column, and a laterally projecting armupon which the drill-head is adjustably mounted. Power to rotate the drill spindle and to feed it vertically in the drill-head is usually provided by a motor or other prime-mover located either on a rearward extension of the arm or on the base at the foot of the column, and the power therefrom is transmitted through suitable mechanism to a shaftjournaled lengthwise of the radial arm, and thence through suitable change-gear mecha-, nism to the drill spindle.

' As is well understood by those skilled in the art, it is essential that means be provided for regulating the speed of rotation of the drill spindle inasmuch as the varyingdiamters of the 'drills and taps and the nature of the work being operated on, each present working conditions which require diiierent speeds of rotation of the spindle to produce maximum efiiciency inoperation.

To provide these various speeds, it has heretofore been customary to locate, adjacent the prime-mover, a change-gear mechanism capable of transmitting about six different speeds from a single speed received from the prime mover. The differences in ratio afforded by this so-called speed-box control are necessarily small since there is considerable mechanism actuated thereby and great diiferences in ratio would effect abrupt changes and cause strains that would be detrimental to the parts.

Coarser changes are provided by a changeear mecahnism located in the drill-head. These latter change gears are known as the back-gears and usually provide four speed changes which multiply the speeds provided by the speed-box into about twentyfour' speeds in the spindle. Inasmuch as only the spindle rotating and translating mechanism is actuated by the baclsgears, the speed changes provided therein may be materially greater than those provided in the speedbox.

Another well known way of providing the necessary number ofspeed changesis to re place the single speed prime mover and the speed-box with a variable speed motor capable of being operated at a plurality of speeds corresponding to the speeds produced in other machines by the speed-box, and combining therewith the usual back-gears in the drill-head. v

T 0 effect a predetermined speed in the spindle, it has heretoforebeen necessary for the operator first, by the manipulation of certain control levers carried by the drill-head, to shift the baclr-gears and thereby obtain the nearest approximate speed obtainable therein; and then, to leave his position at his work and go to theopposite end of the machine where, by manipulation of the speedbox control lever, r the motor controller whichever the case may be, effect the finer and more accurate speed setting. This remote and inconvenient location of the linerv speed regulating mechanism makes its frequent manipulation unhandy and bothersome and therefore the tendency of the operator is to ignore the finer speed settings and to utilize the nearest speed obtainable in the back-gears, which he may'shift from a position at his work. This employment of the improper spindle speed necessarily reduces the efficiency of the machine-tool.

Another disadvantage of these prior 'constructions is that inasmuch as great power must frequently be transmitted at slow speed the parts of the transmission must necessarily be made of a size and strength su'liici'cnt to withstand the strain imposed during such slow transmission and therefore the parts are unduly heavy and objectionable at the time when the mechanism must be driven at a materially faster rate. i

This invention has for an object to provide a radial drill with a constant speed prime mover and a constant speed power transmission extending into the drill-head,

I the latter will not be adj ustably mounted on the arm, and to locate all of the speed change mechanism within the adjustably mounted drill-head; thereby providing a constant speed driving connection from the prime mover to the drill-head,

drive to actuate various other mechanisms provide means selectively to rotate the spindle of a'radial drill at any one of a plurality of different speeds and to provide means to translate the spindle in the drill head, and so to arrange the spindle rotating mechanism and the spindletranslating mechanism that affected by variations in the former.

Still another object of this invention is to combine entirely within the drill-head, a plurality of sets of speed change devices operative in conjunction with. the usua back-gears to produce thirty-two speeds in thespindle from a single speed inthe prime mover.

A further object of this invention is to provide in a radial drill a spindle and means selectively to rotate it at any one of the usual number of speeds and to provide means u n-,

affected by the changes in speed in the spindle for translating the arm on the column and for translating the drill-head on the arm.

Another object of this invention is to provide, in a radial drill having an arm shaft and means to rotate thespindle from the arm shaft, means to disconnect the spindle from its arm shaft and simultaneously therewith to apply a brake to the spindle rotating means.

Other objects and advantages will be in part indicated in the following description and in part rendered apparent therefrom in connection with the annexed drawings.

To enable others skilled in the art so fully to apprehend the underlying features hereof that they may embody the same in the various ways contemplatedby this invention, drawings depicting a preferred typical construction have been annexed as a part of this disclosure and, in such drawings, like characters of reference denote corresponding parts throughout all the views, of which Fig. l is a side elevation, partly in section of a radial drill embodying the present invention. Fig. 2 is a development of the mechanism contained in the drill-headshowing the means for securing thirty-two speeds in the spindle from a single-speed in the arm shaft and for actuating the spindle translating mechanism independently of the spindle speed changes. Fig. 3 is a detail plan showing the means for actuating the drill-head power traverse from the constant speed arm shaft, the controlling lever for the power traverse being shown as swung upwardly about 90 from its normal position for the sake of clearness. Fig. 4 is a side elevation, partly in section, of the mechanism shown in Fig. 3. Fig. 5 is a section on the line 55 of Fig. 3. Fig. 6 is a side elevation of Fig. 5. Fig. 7 is a left end elevation of the radial arm showing more particularly the means for adjustably mounting a coolant pump and actuating it from the constant speed arm shaft. Fig. 8 is a diagrammatic View showing the gearing at the upper end of the column for transmitting power from the upright power shaft in the column to the arm translating screw and to the horizontal arm shaft. Fig. 9 is a detail view showing a lubricant pump actuated by the constantspeed power transmission.

Referring more particularly to the drawings, the invention is disclosed as embodied in a radial drilling and tapping machine com prising a base 1, an upright column 2, a horizontal arm 3, and the usual tool-head 4 slidably mounted on guides 5 carried by thearm. The column preferably comprises a central post 6, and a sleeve 7 rotatably journaled on the post The arm 3 is formed with a girdle 8 slidably mounted upon the cylindrical portion' 7* of the sleeve 7 and is adaptedto be raised and lowered thereon by means of a screw 9 journaled in bearings 10 and 11 provided by the sleeve and having a threaded engagement with the arm 3 as is usual in this type of machine tool. Rotatably and translatably journaled in the head 4 is a tool-spindle 12 adapted to receive the tools commonly used in radial drilling and tappingmachines. Power torotate and translate the tool spindle, to move the drill-head lengthwise of the arm 3, and to elevate and lower the arm on the sleeve 7 is preferably furnished by a single speed prime mover 13 located in any suitable place, such for example as on the base 1, adjacent the foot of the column 2. This prime mover may consist of a pulley, as shown in the drawings, or if desired, it may consist of a constant speed motor. In the embodiment illustrated, power from the prime mover flows through a horizontal shaft 14 journaled in the base of the column and is transmitted, by bevel gears 15 and 16, to an upright shaft 17 journaled coaxial with the column. The shaft 17 carries, at its upper end, a gear 18 (see Figs. 1 and 8) which, through an idler gear 19, drives a gear 20 fixed upon a shaft 21 journaled in bearings 22 and 2.3 provided by the sleeve 7. A gear 25 is fixed to and rotates with the gear 19. The arm translating screw-9 isadapted to be rotated, in reverse directions from the upright shaft 17. To this end, the screw 9 carries at its upper end a gear 24, and atumbler gear serves to connect the gears 18 and 2% directly as shown in full lines in Fig. 8 to rotate the screw in a direotionto lower the arm or indirectly through gears 19-and 25 as shown in dotted lines in Fig. 8 to rotate the screw in the opposite direction to elevate the arm.

Journaled lengthwise of the arm 3 is a shaft 26 having secured to it at its rear end a bevel gear 27 permanently in mesh with a bevel gear 28 journaled in the girdle and having a splined connection with the shaft 2. From the foregoing, it will be perceived that the arm shaftQfi will be rotated continuously from the prime mover at a constant speed in all of the vertical positions of the arm on the column.

Power is taken from the arm shaft and delivered to a shaft 29, rotatably journaled in the drill-head, by a frictional reversing clutch mechanism C which is similar in construction to that forming the subject of Reissue Patent No. 14,755 dated Nov. 18, 1919, to H. M. Norris; This reversing mechanism comprises bevel gears 30 and 31 loosely journaled on a sleeve 32 splined to the shaft 26 and permanently meshing with the opposite sides of a bevel gear 33 carried by the shaft 29. Either of the gears 30 or 31 selectively may be securcdto th'e'sleeve by frictional clutches controlled by a shiftable collar 3-2; as fully explained in said patent. The collar 34. may be shifted to either of its operative positions by a lever 35' located within easy reach of the operator when stationed at his work. It will readily be perceived that inasmuch as the gears 80 and 31 act upon the gear 33 at diametrically opposite sides they will transmit to said gear oppositely directed rotary motion.

The motion received by the gear and shaft 29 is transmitted to the spindle 12 through suitable speed change mechanisms which provide means for varying the speed of rotation of the spindle. Thus, by the manipulation of suitable levers carried by the drill-head the gears of the speed change mechanisms may be so meshed as toproduce the speed best suited to the tool being used and to the work being operated on. As shown in Fig. 2, these speed changes may be effected by three separate change gear-set X, Y and Z. The gear set X comprises gear units 36 and 37 spliued upon the shaft 29 and providing gears 36, 36 and 37 and 37 respectively. These gears are adapted selectively to be meshed with gears 38, 38 and 89, 39 provided by gear units 88 and 39 fixed to a shaft 4-0 also journaled within the drillhead. Thus by selectively meshing these four speeds may be transmitted to the shaft 4:0 from a single speed in the shaft 29.

The gear unit 39 also provides a gear 39 which is adapted to-be meshed with a gear 41 provided by a gear unitel splined to a shaft 42 journaled in the drill-headparallel to the shaft 40. A gear 41 which is adapted to be meshed with the gear 39 is also provided by thegear unit 41-1. The gears 39, 39, 41 and al constitute the gear set Y which serves to double the four speeds produced by the gear set X. i I The tool spindle 12 is trauslatably but nonrotatably journaledin a sleeve d3 jourualed in the drill-head a. Rotation is transmitted from the shaft 42 to the sleeve and thereby to the spindle by means of the gear Z usually known as the backgears which provide four speeds thereby multiplying the eight speeds in the shaft 42 into thirty -two speeds in the spindle. This gear set comprises a gear unit 44 splined to the shaft l2 and providing a gear 4A anda clutch-member a l". llotatably journaled on the sleeve-(l3 is a gear unit 15 providing a gear 45 with which the i l adapted to be meshedyand a gear 45 pern'ianently in mesh with a 16* provided by a gear-unit 4L6 secured upon a shaft l? journaled in line with the shaft l-FZ. The

ear-unit 16 also )rovides a clutch member 5! 46 adapted to be engaged by the clutch member ie l A small gear4l8, later to be referred to, also is secured to 'the shaft ll. Splined lo the sleeve. ll) is a gear-unit 49 providing a gear 419, adapted to mesh with the gear 48,

and clutch member 49 adapted to engage the gear 45 From the foregoing it will be seen that the unit 415 may be rotated either by the gear 41% or by the gear 16 through the clutch 4rd -+4e6 i By shifting the clutch member 49 into engagement with the gear 45 these two ds are transmitted to the sleeve l3 and th l .y to the spindle. The gear unit 46, and thereby he shaft 1-? and gear 48, also receives twospeeds from each speed in the shaft 42. @ne of these speeds is obtained through the engagement of the clutch members 4-1" and 46 and the other is obtained through gears 4.4, 45, 45 and 46. Thus by selectively meshingth gears and clutches any one of thirty-two speeds may be produced in the spindle from a single speed in the arm shaft.

Intermediate its'ends the spindle 12 is ro tatably journaled in sleeve 50 translatably but non-rotatably journale'd. in the drill-head i. Thrust-bearings Bland 52 carried by the spindle at the opposite'ends of the sleeve prevent relative axial movement between the spindle and the sleeve. A toothed rack 53 carried by the sleeve 50 is engaged by a pinion 54L rotatablyjourualed in. the dril -howl and therefore rotation of the pinion. by ins later to be described, causes vertical movement of the sleeve 50 and the tool spindle to cause the tool carried by the latter to penetrate and emerge from the work.

Power to rotate the pinion 54 thereby to translate the tool spindle is preferably taken l El 0 from the constant speed shaft 29, independent of the change gears'thereon. This is efiected through a gear fixed to the shaft 29 which meshes with and drives a gear 56 carried by a shaft 57 also journaled vertically in the, drill head. Fixed upon the shaft 57 is a cone of gears Comprising gears 58, 59, 60, 61,62 and 63 maintained permanently in mesh with gears 64:, 65, 66, 67, 68 and 69, respectively, loosely journaledon a hollow shaft 70 rotatably carried by the drill-head. The shaft 70 is formed in one side with a slot 71 through which is adapted to project the head '72 of a spring pressed drive key 72 pivoted within a slot 73 in a rod 7 1 axially movable in the hollow shaft 70. annular rack-teeth 7 5 which mesh with a pinion 75 adapted to be rotated by a lever '56 carried by the drill-head 4. By shifting the rod 7 1 lengthwise the head '72 of the key 72 may be caused selectivelyto engage any-one of'a plurality of notches '22 formed in the gears 6st, 65, 66, 67, 68 and 69 thereby to effeet a driving connection between the shafts 57 and 70 at any one of 81X available speeds.

To the shaft 70 is secured a worm ii which meshes with a worm-wheel 78 secured to the pinion 5%. Thus it will be seen that means is provided for translating the drill-spindle from the constant speed shaft 29. and that the rate of translation may be varied without affecting the speed of rotation of the drill spindle and viceversa. The shaft '4'0 may also be rotated by a hand-wheel 7 9 having a notch 79 which engages a drive-key 80, also carried by the rod 7 1, and projecting through a slot 81in the shaft 70. The keys 72 and are so arranged that the manual feed is effective only when the key 7 2 is in its intermediate position, as shown in Fig. 2, in which the power feed is ineffective.

The constant speedarm shaft-is also ut1- lized to actuate a power t averse for the drillhead. This traverse CO1 prises a shaft 82 journaled in thedrill-head and carrying a worm 83 adapted to drive a worm Wheel 84: carried by one end of a shaft 85 also journaled in the drill-head. The opposite end of the shaft 85 carries a pinion 86 meshing with a rack-bar 87 secured lengthwise of the radial arm. Thus rotation of the shaft 82 in one direction effects translation of the. drill-head toward the column and rotationof the shaft in the opposite direction translates the head awayfrom the column. Power to rotate the shaft 82 is taken from the arm shaft by a gear 89 rotatably journaled in the drill-head and having a splined connection with said arm shaft. The gear 89 drives a similar gear 90 carried by a shaft 91 journaled in the drill head and carrying at one end a pulley 92.

. Also journaled in the drill-head, in bearings 93 and 941 is a shaft 95 carrying at its upper end a pulley 96 adapted to be driven, by a belt 97, from the pulley 92. The shaft 95 carries,

The roe 74 is formed with at its lower enda bevel gear 98 permanently in mesh with bevel gears 99 and 100 loosely journaled on the shaft 82 and adapted selectively to be clutched by a shi'ftable clutch element 101 carried by a rod 103 slidably mounted in the shaft 82. For the purpose of shifting the clutch member 101, there is attached to the rod 103, by means of a pin 10% passing through slots 105 in the shaft 82, a cylindrical rack 106 which is engaged bya pinion 107 carried by a shaft 108 rotatably and translatably journaled in the drill-head 4. Man-' ual means also is provided to rotate the shaft 82 to velfect translation of the drill-head. Thiscomprises a hand wheel journaled coizial with the shaft 82 and carrying a clutchelement 109 which is adapted to be engaged by a similar clutch element 110 splined to the shaft 82. A spring controlled bell-crank lever 111, pivoted at 112, normally holds the clutch-elements 109 and 110 together to connect the manual drive for the shaft 82; As

shown in Fig. 3, the lever 111 has a portion bearing against the p1nion and therefore inward movement of the pinion, prior to its rotation to shift the clutch member 101, swings the bell-crank about its pivot and disconnects the clutch elements 109 and 110. A lever 113 pivoted to the shaft 108 serves to translate and rotate that shaft.

To overcome the momentum of the drillhead and its translating mechanism when power drive is rendered inefiective, the shaft 82 carries a brake-drum 114 adapted to be engaged by a brake-shoe 115 carried by a spring-pressed lever 116 pivotedat 117 in the drill-head. During the power traverse of the drill-head the brake-shoe is held out of engagement with the brake-drum by a cam 118 which is forced into contact with the lever 116 by a cam 119 on the shaft 108. lVhen the lever 113 is moved to shift the clutch member 101 to its neutral position the low portion of the cam 119 is brought adjacent the bar 118 attached to the cam 118, thereby permitting the cam 118 to be moved back from the lever 116 whereupon the spring .9 attached to the lever 116 forces the brake shoe into contact with the brake drum. 7

The constant speed power transmission from the prime mover to the drill-head may also be utilized to great advantage to operate a coolant pump to supply a constant stream of coolant to the tool. This pump may be located at any suitable place and connected with any part of the constant speed transmission but it is preferably carried by the girdle 8 of the arm and driven from the arm shaft 26. As shown in Fig. 7, a pump P is carried by a base 120 pivotally supported at 1 1 upon a bracket 122, affixed to the girdle 8. A continuous belt 123 passes about the pump pulley and is driven from a pulley 124 on the arm shaft 26. It will readily be perceived that due to the location of the pivot 121 the pump drawn up by the pump is forced through a flexible tube 127 and delivered by a nozzle 128 to the tool.

Still another advantage gained by the use of a constant speed transmission to the drillhead is that this transmission may be used more effectively and more satisfactorily to actuate a continuous lubricating system for the gears and hearings in thedrill-head. Fig. 9 shows a r servoir 7' formed in the drill-head and lubricant pump L actuated from the constant speed shaft 29, journaled in the drill-head, through bevel gears 129 and 130. Inasmuch as the rest of the lubricating system for the gears and bearings in the drill head is substantially the same as that shown in United States patent to D. C. Klausmeyer No 1,653,576 dated Dec. 2, 1927, further illus trait-ion and description thereof is deemed unnecessary in this application.

From the foregoing, it will be seen that many advantages have been gained by pro viding a constant speed transmission from the prive mover to the drill-head. Not only does this constant speed transmission permit the convenient manipulation of all of the speed change devices from the operators po sition at his work but it also permits all of the trains of mechanism to be actuated inde- ')endently of the speed of rotation of the spindle.

Without further analysis, the foregoing will so fully reveal the ist of this invention that others can, by applying current knowl edge, readily adapt it for various utilizations by retaining one or more of the features that, from the standpoint of the prior art, fairly constitute essential characteristics of either the generic or specific aspects of this invention and, therefore, such adaptations should be, and are intended to be, comprehended within the meaning and range of equivalency of the following claims.

Having thus revealed this invention, We claim as new and desire to secure the following combinations and elements, or equivalents thereof, by Letters Patent of the United States:

1. A radial drill combining a column; an arm supported by the column; a drill-head carried by said arm; a spindle rotatably journaled in the drill-head; a constant speed power transmission extending along said arm; and three serially arranged and independently cont-rolled gear sets embodied in said head for variably driving said spindle from said single speed power transmission.

"2. A radial drill combining a column; an arm supported by the column; a drill-head adj ustably mounted on the arm; a spindle rotatably jot naled in the drill-head; a tool carried by the spindle; a shaft extending len 'thwise of the arm; a single speed primemover coimected to rotate said arm shaft at u constant we; speed change mechanism embodied in at a plurality of 17.11.. s from said arni shaft; means actuated by said arm shaft to translate the drill-head on the arm; a reservoir; and "a coolant 'tem' including a pump actuated by saidcon nt speed arm shaft to draw coolant from, said reservoirandapply it to said tool.

3. A radial drillcomhininr; a column; an arm extending horizontally from said column; a drill-head adjustably mounted on the arm a s giindlerotatably jo'urnaled in said drill-head; a single speed prime-mover adiacent the base of the column; a. shaft operati, ely connected. with the 'irime-mover and extending upwardly through the column; a

screw journalcd extericrly of said column and having a tin aded connection with said arm;

a second shaft iour'naled exteriorly of said column sin gle speed driving means connectr 1 irst named shaftwith said screw and y 1. 1h aid second shaft; a shaftjournaled lengthwiseof said arm; sin le speed driving connection between said second shaft an d said arml shaft; means actuated by said single speed arm shaft to translate said drill-head on said arm and a plurality of independently operative speed change devices also located in said drill-headand connecting said arm shaft with said spindle to rotate the tool at variousspeeds. I

4c. A,radialdrillcombininga column; an arm supportedby the column; a drill-head earrie'dby thearm; a spindle rotatably and translatably journaled in the drill-head; a constant speed power transmission extending along said arm; means carried'by said drillhead for selectively rotating'said spindle at any one of more than six speeds from the single speed in the constant speed transmission; andmeans operated directly from the constant speed transmission for translating the spindle '5. A radial drill combining a eolumnyan arm supported by the column; a drill-head carried by the arm; a spindle rotatably and tr'anslatably journaled in the drill-head; a

constant speed power transmission extending said head for rotating said spindle carried by the arm; a spindle rotatab-ly and translatably journaled in the drill-head; a prime mover; a constant speed power transmission operatively connected With said prime mover and extending along saidarm; means carried by the drill-head and actuated by said constant speed transmission for rotating said spindle at anyone of a plurality of speeds;

- means carried by the drill-head and actuated said fourth shaft.

directly from said constant speed transmission for translating said spindle; and means for varying the speed of rotation and speed of translation of the drill spindle each without affecting the other.

7. In a radial drill, a drill-head; a constant speed power shaft transmitting power to said drill-head; a constant speed shaft journaled in said drill-head and adapted to be rotated from said power shaft; a spindle rotatably and translatably journaled in the drill-head; spindle rotating means comprising a plurality of sets of speed change gears for selectively rotating said spindleat any one of a considerable number of speeds from the single speed insaid constant speed shaft; a spindle translating mechanism actuated by said constant speed shaft independently of said spindle rotating means; and means to vary the speed of translation of said spindle.

8. In a radial drill, an arm; a drill-head mounted on the arm; a constant speed power shaft carriedby the arm and transmitting power to said drill-head; a second shaft, journaled in the drill-head and rotated by said power shaft at an invariable speed; a spindle rotatably and translatably journaled in the drill-head; a plurality of sets of speed change gears intermediate the said second shaft and the spindle; a third shaft geared to said second shaft; means actuated by said third shaft to translate said spindle, said means including a fourth shaft; a cone of gears on said third shaft; a cone of gears loosely ournaled on said fourth shaft, said'cones of gears being permanently in mesh; and means to render any pair of said gears to transmit power to I 9. A radial drill combining'a column; an arm supported by the column; a drill-head carried by the arm; a constant speed shaft journaled lengthwise of said arm; a second constant speed shaft, journaled in said drillhead and driven by said arm shaft; a drill spindle rotatably journaled in said drillhead ;a plurality of sets of speed change gears operatively connecting said second shaft with said spindle for rotating said spindle-at any one of a plurality of speeds; a reservoir in the drill-he ad anda lubricant pump driven by said second constant speed shaft and adapted to take lubricant from said reservoir and apply it to said gears.

10. A radial drill combining, an upright 7 column; a horizontally disposed arm supported by said column; a tool-headadjust ablymounted on thearm a spindle rotatably journaled in said tool-head; a single speed prime mover located remote from said toolhead; a power transmission extending lengthwise of said arm; a single speed driving con- HENRY M. NORRIS. DAVID C. KLAUSMEYER. 

